<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <style>
    .left {
      width: 100px;
      height: 200px;
      background: salmon;
      float: left;
    }

    .right {
      height: 300px;
      background: seagreen;
      overflow: hidden;
    }
  </style>
</head>

<body>
  <div class="left"></div>
  <div class="right"></div>
</body>

</html>